Design and Fabrication of Micro Optical Film by Ultraviolet Roll Imprinting

Abstract

Mossbauer and x-ray diffraction measurements have been made on M,~xFe,(PyNO),(C10,)2, where M is Zn or Mg, for 0 < x s 1. It has been possible to reproduce the Mossbauer spectra reasonably well using a model in which the ferrous ions experience a small off-axial distortion from the nominal trigonal (C3J site symmetry. The Mossbauer results indicate that the proportion of Fe" ions in sites that are distorted from trigonal symmetry varies as a function of iron concentration in the Zn-Fe series but remains apparently invariant across the Mg-Fe series. The unit-cell volume of these compounds was found to exhibit a strong non-linear dependence on composition for the Zn-Fe system, whereas a roughly linear relation was found for the Mg-Fe system. Furthermore, the behaviour of the unit-cell volume appears to be correlated with the composition-dependent changes in the proportion of ferrous ions distorted from C3, site symmetry.

Recent developments and design challenges in continuous roller micro- and nanoimprinting

“…60 However the epoxysilicone resin requires an adhesion promoter to be deposited on glass substrates and for high density features on PET substrates in order to prevent delamination and sticking to the ETFE mold. 61 Another investigation into UV roller imprinting was reported by Ahn et al 24,56 Their setup is similar to that shown in Fig. In particular, sub-100 nm linewidth gratings were fabricated and shown in cross-section.…”

“…In particular, sub-100 nm linewidth gratings were fabricated and shown in cross-section. 56 They also performed mold replication with UV-curable silicone urethane acrylate photopolymer in order to form thin polymer sheet molds which could also be wrapped around an aluminum base roller. 55 More recently, Guo has unveiled a newly completed six-inch roll-to-roll and roll-to-plate capable apparatus and demonstrated four-inch wide continuous imprinting of somewhat larger 300 nm linewidth and 700 nm period gratings (see Fig.…”

“…60 In an earlier report they used a similar UV roller imprinting apparatus to fabricate wire grid polarizers on 10 mm wide PET strips. 56 Thus, Ahn et al reported large area UV roller imprinting of features with both seamed and seamless roller molds; direct micro-machining on the roll of course being their seamless approach. 16).…”

“…16). 56 Such features are useful for increasing the viewing angle in projection displays. UV curing of the imprinted resin takes place between the two rollers under the pressure provided by the belt tension.…”

“…Of course, there are established techniques for fast, large-area writing of patterns onto a cylindrical roller surface, such as laser micro-machining, 82 precision milling, 56 and wet-etch based lithographic processes. In particular for beam writing and mask exposure techniques, it is difficult to achieve uniform exposure of the resist on curved surfaces or cylinders because the angle of incidence relative to the surface can change from one exposure site to the next.…”